Comparison against 25 SATA 240-256 GB SSD's

By Koen CrijnsFriday 7 March 2014 14:59

Introduction

Plextor is first to the market with a native PCI-Express SSD for desktop PC's, the M6. Is it good enough to make the abundance of current available SATA 600 SSD's look obsolete? Hardware.info tests the 256GB version of the M6 to find out

It will not come as a surprise to our regular readers that the Serial ATA 600 interface has been the bottleneck for SSD performance for some time now. The maximum throughput of 600MB/Sec (550 MB/sec in real life applications) is being achieved by virtually every SSD of the latest generations. The small differences that are still there are mainly down to random read and write perfomance and the steady state performance between the different drives. As we have already explained in a background article last year the SATA 1200 standard is not something we can expect to be a reality in the near future, as the leap from SATA 600 to 1200 is not as simple as it would seem.

Luckily there is a solution to the SATA 600 bottleneck, the PCI-Express bus, mainly used for dedicated graphics, sound or RAID cards as well as for controller chips on modern motherboards, offers a much higher theoretical throughput than SATA. The PCI-EXpress bus is also very suitable for storage, and as PCI-E offers 500MB/s per lane speed can be 2GB/sec when combining 4 lanes. There are already a few different form factors to use PCI-Express SSD's in PC's, laptops have the M.2 standard (also known as NGFF), the sucessor to mSATA. These SSD's can be used with either the SATA bus or a PCI-Express x2 bus. For Desktop PC's a SATA Express bus is in development, with which PCI-Express SSD's in 2,5" format will be possible. However the SATA express bus development is not coming soon, as we have not seen any announcements of SATA Express products and it is still uncertain that Intel will make use of this standard in there next generation chipsets. This is causing some controversy, as itis now possible to use faster SSD's in laptops and ultrabooks than we can in high end PC's.

SSD-manufactorers seem to be losing their patience, as the need for ever faster drives is more apparent for desktop PC's but the development appears to have slowed down significantly. Plextor is the first to use an unorthodox method to up the speed stakes for PC's, and has introduced a M.2 SSD sporting a M.2 to PCI-Express converter. This makes it possible to use the SSD without any problems in a PCI-Express x4 or x16 slot as the controller used is native PC-Express, not a PCI-E to SATA converter. This makes it possible for Plextor to promise transfer speeds of more than 700MB/sec and they can boast to have the first native PCI-Express SSD for consumer PC's.